The Common Screwpine (Pandanus utilis) is a tropical tree species native to Madagascar and contrary to what it´s name implies it is NOT a pine tree. It does not even remotely resemble a pine tree so why the name - I have no idea. At any rate it is an interesting tree species and one that is often grown as an ornamental tree in climates that permit. An alternate spelling for the common name is "Madagascar Screw-pine".
The younger trees in this species have very little branching but as they get older they develop long thin branches a sort of "Dr. Seus" look. It also reminds me a it of the Dragon tree. This tree also has a tendency to grow auxiliary "prop-roots" to help support the weight of the tree. There is a better image of these tube like roots below.
The image below is of a new flower forming at the base of the long, thin, spiny leaves.
The flower then opens up like you can see in the image below as a hanging, almost palm inflorescence-like structure.
When the new fruit starts to from it looks at first like a small (softball size) ball covered with molar-like teeth. At least this is what it looks like to me anyway.
This ball eventually grows to about the size of a volleyball or small indoor soccer-ball. The seeds of this tree fruit are edible but not very tasty. There is a similar Pandanus tree in Papua New Guinea that grows fruits that are about 2 feet long and 4-5 inches wide. Its seeds are quite a bit smaller than these and the mature fruit can be red or yellow. It is a favorite meal for the locals who boil it in water and then suck the juice off the seeds and then spit the seeds out.
The "bark" of this tree is somewhat abrasive although is wears smooth with time. The leaf margins have small thorn-like spines that can scrape and irritate the skin.
Other tropical trees...
Another strange looking tree is the Monkey Puzzle tree.